Comparison of monosaccharide composition of capsular polysaccharides in Streptococcus suis serotype 1，2，14 and 1/2

Abstract:

Abstract:［Objective］There are one-way or two-way cross-reactions among Streptococcus suis serotype 1，2，1/2 and 14，the reason to which was unknown． ［Methods］ The capsular polysaccharides of serotype 14 and 1/2 were purified on Sephacryl S-300 column and identified by phenol-sulphuric acid method and dot-ELISA．The molecular weight of the serotype 14 and 1/2 capsular polysaccharides was revealed as 487.38 kDa and 512. 72 kDa by high performance gel permeation chromatography，respectively.［Results］The monosaccharide composition of serotype 14 and 1/2 capsular polysaccharides was determined as Glc/Gal/GlcNAc/Rha/Neu5Ac (1:2.94:1.35:0.24:0.37) and Glc/Gal/GlcNAc/GalNAc/Rha/Neu5Ac (1:1.67:1.05:0.93:0.72:0.7)by pre-column derivatization high performance liquid chromatography，fluorescent labeling HPLC and NMR，respectively．These were compared with the composition of serotype 1 and 2 capsular polysaccharides．Glc，GlcN，Gal and Neu5Ac was contained in the capsular polysaccharides of serotype 1，2 14 and 1/2．But there is no prominent correlation between the monosaccharide composition and crossreactions．The cross-reactions among them could be induced by the structure of the capsular polysaccharides and/or the other components on the cell wall．

Key words:Keywords: Streptococcus suis，serotype，capsular polysaccharide，monosaccharide composition